Click
here to close Hello! We notice that
you are using Internet Explorer, which is not supported by Echinobase
and may cause the site to display incorrectly. We suggest using a
current version of Chrome,
FireFox,
or Safari.
???displayArticle.abstract???
This review summarizes and integrates our current understanding of how sea stars make gametes. Although little is known of the mechanism of germ line formation in these animals, recent results point to specific cells and to cohorts of molecules in the embryos and larvae that may lay the ground work for future research efforts. A coelomic outpocketing forms in the posterior of the gut in larvae, referred to as the posterior enterocoel (PE), that when removed, significantly reduces the number of germ cell later in larval growth. This same PE structure also selectively accumulates several germ-line associated factors-vasa, nanos, piwi-and excludes factors involved in somatic cell fate. Since its formation is relatively late in development, these germ cells may form by inductive mechanisms. When integrated into the morphological observations of germ cells and gonad development in larvae, juveniles, and adults, the field of germ line determination appears to have a good model system to study inductive germ line determination to complement the recent work on the molecular mechanisms in mice. We hope this review will also guide investigators interested in germ line determination and regulation of the germ line into how these animals can help in this research field. The review is not intended to be comprehensive-sea star reproduction has been studied for over 100 years and many reviews are comprehensive in their coverage of, for example, seasonal growth of the gonads in response to light, nutrient, and temperature. Rather the intent of this review is to help the reader focus on new experimental results attached to the historical underpinnings of how the germ cell functions in sea stars with particular emphasis to clarify the important areas of priority for future research.
Ancelin,
Blimp1 associates with Prmt5 and directs histone arginine methylation in mouse germ cells.
2006, Pubmed
Ancelin,
Blimp1 associates with Prmt5 and directs histone arginine methylation in mouse germ cells.
2006,
Pubmed
Byrne,
Embryogenesis and Larval Development of the Asteroid Patiriella regularis Viewed by Light and Scanning Electron Microscopy.
1991,
Pubmed
,
Echinobase
Campanale,
Programmed reduction of ABC transporter activity in sea urchin germline progenitors.
2012,
Pubmed
,
Echinobase
Eaves,
Reproduction: widespread cloning in echinoderm larvae.
2003,
Pubmed
,
Echinobase
Erwin,
The Cambrian conundrum: early divergence and later ecological success in the early history of animals.
2011,
Pubmed
Ewen-Campen,
The molecular machinery of germ line specification.
2010,
Pubmed
Extavour,
Mechanisms of germ cell specification across the metazoans: epigenesis and preformation.
2003,
Pubmed
Foltz,
Echinoderm eggs and embryos: procurement and culture.
2004,
Pubmed
,
Echinobase
Fresques,
Selective accumulation of germ-line associated gene products in early development of the sea star and distinct differences from germ-line development in the sea urchin.
2014,
Pubmed
,
Echinobase
Hayashi,
Germ cell specification in mice.
2007,
Pubmed
Hernroth,
Possibility of mixed progenitor cells in sea star arm regeneration.
2010,
Pubmed
,
Echinobase
Hines,
Androgen metabolism in somatic and germinal tissues of the sea star Asterias vulgaris.
1992,
Pubmed
,
Echinobase
Hinman,
Expression of AmKrox, a starfish ortholog of a sea urchin transcription factor essential for endomesodermal specification.
2003,
Pubmed
,
Echinobase
Hinman,
Developmental gene regulatory network architecture across 500 million years of echinoderm evolution.
2003,
Pubmed
,
Echinobase
Inoue,
Germ Cell Differentiation in Starfish: The Posterior Enterocoel as the Origin of Germ Cells in Asterina pectinifera: (starfish/germ cells/PGC/posterior enterocoel/haemal sinus).
1992,
Pubmed
,
Echinobase
Inoue,
Origin of Germ Cells and Early Differentiation of Gonads in the Starfish, Asterina pectinifera: (starfish/germ cells/PGC/gonad/haemal sinus).
1991,
Pubmed
,
Echinobase
Jaeckle,
Multiple Modes of Asexual Reproduction by Tropical and Subtropical Sea Star Larvae: an Unusual Adaptation for Genet Dispersal and Survival.
1994,
Pubmed
,
Echinobase
Jaffe,
Quantitative microinjection of oocytes, eggs, and embryos.
2004,
Pubmed
Juliano,
Developmental biology. Versatile germline genes.
2010,
Pubmed
Juliano,
An evolutionary transition of Vasa regulation in echinoderms.
2009,
Pubmed
,
Echinobase
Knott,
Identification of asteroid genera with species capable of larval cloning.
2003,
Pubmed
,
Echinobase
Kuraishi,
Cell Movements during Gastrulation of Starfish Larvae.
1992,
Pubmed
,
Echinobase
Livi,
Expression and function of blimp1/krox, an alternatively transcribed regulatory gene of the sea urchin endomesoderm network.
2006,
Pubmed
,
Echinobase
Luo,
Opposing nodal and BMP signals regulate left-right asymmetry in the sea urchin larva.
2012,
Pubmed
,
Echinobase
Morris,
Development of the five primary podia from the coeloms of a sea star larva: homology with the echinoid echinoderms and other deuterostomes.
2009,
Pubmed
,
Echinobase
Oulhen,
Dysferlin is essential for endocytosis in the sea star oocyte.
2014,
Pubmed
,
Echinobase
Pehrson,
The fate of the small micromeres in sea urchin development.
1986,
Pubmed
,
Echinobase
Ransick,
Postembryonic segregation of the germ line in sea urchins in relation to indirect development.
1996,
Pubmed
,
Echinobase
Seervai,
Lessons for inductive germline determination.
2013,
Pubmed
Smith,
The oldest echinoderm faunas from Gondwana show that echinoderm body plan diversification was rapid.
2013,
Pubmed
,
Echinobase
Tanaka,
Study of the Lineage and Cell Cycle of Small Micromeres in Embryos of the Sea Urchin, Hemicentrotus pulcherrimus: (small micromeres/cell cycle/cell lineage/unequal cleavage/sea urchin).
1990,
Pubmed
,
Echinobase
Vandenberg,
A unified model for left-right asymmetry? Comparison and synthesis of molecular models of embryonic laterality.
2013,
Pubmed
Vickery,
Effects of food concentration and availability on the incidence of cloning in planktotrophic larvae of the sea star Pisaster ochraceus.
2000,
Pubmed
,
Echinobase
Vickery,
Utilization of a novel deuterostome model for the study of regeneration genetics: molecular cloning of genes that are differentially expressed during early stages of larval sea star regeneration.
2001,
Pubmed
,
Echinobase
Voronina,
Vasa protein expression is restricted to the small micromeres of the sea urchin, but is inducible in other lineages early in development.
2008,
Pubmed
,
Echinobase
Wessel,
Use of sea stars to study basic reproductive processes.
2010,
Pubmed
,
Echinobase
Yajima,
Autonomy in specification of primordial germ cells and their passive translocation in the sea urchin.
2012,
Pubmed
,
Echinobase
Yajima,
Small micromeres contribute to the germline in the sea urchin.
2011,
Pubmed
,
Echinobase